CVS drugs and pharmacology

Question 1

What receptors do epinephrine and norepinephrine act on?

Answer 1

Epinephrine: a and B adrenoreceptors.

Norepinephrine: a1 and 2, B1 adrenoreceptors

Question 2

Action of epinephrine at B1 and B2 adrenoreceptors?

Answer 2

B1: Vasoconstriction and cardiac stimulant. Raises Systolic BP.

B2: Vasodilation at skeletal muscle blood vessels.

Question 3

Action of norepinephrine at receptors?

Answer 3

Increases peripheral resistance and systolic/diastolic bp.

Question 4

MOA and use of phenylephrine?

Answer 4

Is a selective a-1 adrenoreceptor agonist.
Causes vasoconstriction and raises bp.

Is used as a nasal decongestant, pupil dilator and vasopressor (e.g in postural hypotension).

Question 5

i) MOA. and use of salbutamol?

ii) SE of salbutamol?

Answer 5

B adrenoreceptor agonist.
Causes vasodilation and drop in BP and relaxes smooth muscle.

Used inhaled to treat asthma (bronchodilation due to relaxation of airway smooth muscle).

SE= Arrythmias, Tachycardia, Headache

Question 6

i) MOA and use of Phenoxybenzamine?

ii) SE’s of selective a-1 adrenoreceptors?

Answer 6

an adrenoreceptor antagonist. Blocks norepinephrine binding and prevents it’s reuptake.
Causes vasodilation and drop in BP and PR.

SE: Postural hypotension and impotence.

Question 7

MOA and uses of Propranolol and Atenolol?

Answer 7

Propranolol: B blocker.
Atenolol: B blocker (B1, cardioselective)
- Treat cardiac arrhythmias, angina, MI, anxiety.
- SE: Bronchoconstriction, bradycardia, HF, cold extremities, insomnia, depression.

Question 8

Features of Nicotinic receptors?

Answer 8

• Ach binds, influx of Na+ and efflux of K+, prop of AP, Ca2+ release, activation of contractile machinery.
• Ligand-gated ion channels
• Fast excitary transmission
• Nm and Nn types

Question 9

Features of Muscarinic receptors?

Answer 9

• M1, M2, M3 types.
• M1 and 3 acts via IP pathway (prod. IP3 and DAG)
• M2 inhibits adenylate cyclase (inhibit cAMP).

Question 10

MOA and use of Pilocarpine?

Answer 10

Direct muscarinic agonist.
Increases sec. by exocrine glands.
Binds to M3 rec, prod. IP3 and DAG, Ca2+ release, binds to caldesmon, actin-myosin interactions, muscle contracts.
Can be used to treat glaucoma (drains aqueous humour)

Question 11

MOA. and use of Nicotine?

Answer 11

Direct nicotinic agonist.
Binds to both Nm and Nn.
Can be used in smoking cessation.
Causes vasoconstriction and increases bp.

Question 12

MOA, uses and examples of Anti-acetylcholinesterases?

Answer 12

Bind to AchE, prevent hydrolysis of Ach, therefore increase the effects of Ach.

• Short acting (Edrophonium)
• Used to diagnose MG.
• Medium acting (Neostigmine, Physostigmine)
• Treats glaucoma.
• Irreversible (Sarin)
• Insecticides, war gases

Question 13

Consequences of Anti-AchE poisoning?

Antidotes to Anti-AchE poisoning?

Answer 13

SLUDGE Syndrome
Bradycardia 
Hypotension 
Hypersecretion 
Bronchoconstriction 
GIT hypermotility 
Increased intraocular pressure. 

Antidote?

• Atropine
• Oxime

Question 14

MOA and use of Atropine?

Answer 14

Cholinergic receptor antagonist.(comp)
Causes pupil dilation, inhibits secretions.

SE: Restlessness, agitation, disorientation, body temp increase.

Question 15

MOA of Nitrates in treating Angina and other uses?

Answer 15

Nitrate=> NO=> Activates guanylyl cyclase=> prod. cGMP=> Activates protein kinases=> Phosp. myosin light chains=> Decreases ic Ca2+=> Vascular relaxation.

Route?

• Orally
• Sublingually
• Cutaneously
• IV

Treats?
- SA, UA, MI, HF, Hypertension

SE’s?
- Headache, hypotension (especially with phosphodiesterase 5 inhibitors)

Question 16

Beta blocker functions?

Answer 16

Reduce HR
Reduce contractility
Reduce BP/Afterload

Question 17

MOA of Ca2+ channel blockers in treating Angina and other uses?

Answer 17

Blocks L type Ca2+ channel=> Decreases ic Ca2+=> Decrease heart contractility and relax vasc. sm=> Decreases work of heart.

Treats SA, Arrhythmias, and hypertension

SE’s: dizzyness, hypotension, flushing, peripheral oedema, bradycardia, constipation, HF.

Question 18

What type of anti arrhythmitic is amiodarone?

Answer 18

K+ channel blocker. (Class III A.A drug)